package org.whuims.expertreader.excelreader;

import java.io.*;
import java.util.ArrayList;
import java.util.List;

import org.apache.log4j.Logger;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;


public class PoiReader {
    private Logger logger = Logger.getLogger(PoiReader.class);
    private final static String xls = "xls";
    private final static String xlsx = "xlsx";

    private String filePath;
    private List<Sheet> sheetList = new ArrayList<Sheet>();

    public PoiReader(String filePath) {
        this.filePath = filePath;
    }

    /**
     * 读入excel文件，解析后返回
     *
     * @throws IOException
     */
    public List<Sheet> readExcel() throws IOException {
        File file = new File(this.filePath);
        //检查文件
        checkFile(file);
        //获得Workbook工作薄对象
        Workbook workbook = getWorkBook(file);
        if (workbook != null) {
            for (int sheetNum = 0; sheetNum < workbook.getNumberOfSheets(); sheetNum++) {
                //获得当前sheet工作表
                Sheet sheet = workbook.getSheetAt(sheetNum);
                sheetList.add(sheet);
            }
        }
        workbook.close();
        return sheetList;
    }

    public List<String[]> readSheet(Sheet sheet) {
        //创建返回对象，把每行中的值作为一个数组，所有行作为一个集合返回
        List<String[]> list = new ArrayList<String[]>();

        if (sheet == null) {
            return null;
        }
        //获得当前sheet的开始行
        int firstRowNum = sheet.getFirstRowNum();
        //获得当前sheet的结束行
        int lastRowNum = sheet.getLastRowNum();
        //循环除了第一行的所有行
        for (int rowNum = firstRowNum + 1; rowNum <= lastRowNum; rowNum++) {
            //获得当前行
            Row row = sheet.getRow(rowNum);
            if (row == null) {
                continue;
            }
            //获得当前行的开始列
            int firstCellNum = row.getFirstCellNum();
            //获得当前行的列数
            int lastCellNum = row.getPhysicalNumberOfCells();
            String[] cells = new String[row.getPhysicalNumberOfCells()];
            //循环当前行
            for (int cellNum = firstCellNum; cellNum < lastCellNum; cellNum++) {
                Cell cell = row.getCell(cellNum);
                cells[cellNum] = getCellValue(cell);
            }
            list.add(cells);
        }
        return list;
    }

    public void checkFile(File file) throws IOException {
        //判断文件是否存在
        if (null == file) {
            logger.error("文件不存在！");
            throw new FileNotFoundException("文件不存在！");
        }
        //获得文件名
        String fileName = file.getName();
        //判断文件是否是excel文件
        if (!fileName.endsWith(xls) && !fileName.endsWith(xlsx)) {
            logger.error(fileName + "不是excel文件");
            throw new IOException(fileName + "不是excel文件");
        }
    }

    public Workbook getWorkBook(File file) {
        //获得文件名
        String fileName = file.getName();
        //创建Workbook工作薄对象，表示整个excel
        Workbook workbook = null;
        try {
            //获取excel文件的io流
            InputStream is = new FileInputStream(file);
            //根据文件后缀名不同(xls和xlsx)获得不同的Workbook实现类对象
            if (fileName.endsWith(xls)) {
                //2003格式
                workbook = new HSSFWorkbook(is);
            } else if (fileName.endsWith(xlsx)) {
                //2007格式
                workbook = new XSSFWorkbook(is);
            }
        } catch (IOException e) {
            logger.info(e.getMessage());
        }
        return workbook;
    }

    public String getCellValue(Cell cell) {
        String cellValue = "";
        if (cell == null) {
            return cellValue;
        }
        //把数字当成String来读，避免出现1读成1.0的情况
        if (cell.getCellType() == Cell.CELL_TYPE_NUMERIC) {
            cell.setCellType(Cell.CELL_TYPE_STRING);
        }
        //判断数据的类型
        switch (cell.getCellType()) {
            case Cell.CELL_TYPE_NUMERIC: //数字
                cellValue = String.valueOf(cell.getNumericCellValue());
                break;
            case Cell.CELL_TYPE_STRING: //字符串
                cellValue = String.valueOf(cell.getStringCellValue());
                break;
            case Cell.CELL_TYPE_BOOLEAN: //Boolean
                cellValue = String.valueOf(cell.getBooleanCellValue());
                break;
            case Cell.CELL_TYPE_FORMULA: //公式
                cellValue = String.valueOf(cell.getCellFormula());
                break;
            case Cell.CELL_TYPE_BLANK: //空值
                cellValue = "";
                break;
            case Cell.CELL_TYPE_ERROR: //故障
                cellValue = "非法字符";
                break;
            default:
                cellValue = "未知类型";
                break;
        }
        return cellValue;
    }

    public static void main(String[] args) {
        String filePath = "d:\\expertinput.xlsx";
        try {
            PoiReader reader = new PoiReader(filePath);
            List<Sheet> sheetList = reader.readExcel();
            for (Sheet sheet : sheetList) {
                System.out.println(sheet.getSheetName());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
